The subject matter of the specification relates to telecommunications services.
A private branch exchange (PBX) is a telephone exchange that serves a particular organization. PBXs make connections among the internal telephones of the particular organization—usually a business—and also connect them to the public switched telephone network (PSTN) via trunk lines. Because a PBX incorporates telephones, fax machines, modems, and more, the general term “extension” is often used to refer to any end point on the branch.
With the rapid development of various data networks, for example, packet switching networks, PBX services can now be carried out over these various data networks. Traditional PBX services had previously been difficult to arrange for smaller organizations. Hosted PBX services are developed to serve these smaller organizations. In a hosted setup, the PBX is located at and managed by a service provider, and features and calls are delivered via various data networks (e.g., the Internet and PSTN). The customers just sign up for a service, rather than buying and maintaining expensive PBX hardware.